UNW_IS_SIGNAL_FRAME(3) Programming Library UNW_IS_SIGNAL_FRAME(3)NAMEunw_is_signal_frame-- check if current frame is a signal frame
SYNOPSIS
#include <libunwind.h>
int unw_is_signal_frame(unw_cursor_t *cp);
DESCRIPTION
The unw_is_signal_frame() routine returns a positive value if the cur‐
rent frame identified by cp is a signal frame, and a value of 0 other‐
wise. For the purpose of this discussion, a signal frame is a frame
that was created in response to a potentially asynchronous interrup‐
tion. For UNIX and UNIX-like platforms, such frames are normally cre‐
ated by the kernel when delivering a signal. In a kernel-environment,
a signal frame might, for example, correspond to a frame created in
response to a device interrupt.
Signal frames are somewhat unusual because the asynchronous nature of
the events that create them require storing the contents of registers
that are normally treated as scratch (``caller-saved'') registers.
RETURN VALUE
On successful completion, unw_is_signal_frame() returns a positive
value if the current frame is a signal frame, or 0 if it is not. Other‐
wise, a negative value of one of the error-codes below is returned.
THREAD AND SIGNAL SAFETYunw_is_signal_frame() is thread-safe as well as safe to use from a sig‐
nal handler.
ERRORS
UNW_ENOINFO
Libunwind is unable to determine whether or not the current
frame is a signal frame.
SEE ALSOlibunwind(3), unw_get_reg(3), unw_set_reg(3), unw_get_fpreg(3),
unw_set_fpreg(3)AUTHOR
David Mosberger-Tang
Hewlett-Packard Labs
Palo-Alto, CA 94304
Email: davidm@hpl.hp.com
WWW: http://www.hpl.hp.com/research/linux/libunwind/.
Programming Library 05 August 2004 UNW_IS_SIGNAL_FRAME(3)
